This invention relates to a compact flying printer utilized in electronic desk calculators and other numerical readout devices In such printers, the hammer strikes a selected character from an array of characters provided in columnar fashion on the periphery of a continuously rotating print drum. However, the known arrangements of this type of printer have several substantial drawbacks. Specifically, shear will occur in the printing process if the contact time between the hammer and the print drum is too great, resulting in smudged printing or ripped paper. In order to overcome this defect, the contact time of the hammer with the character must be shortened, thereby increasing the operating speed of said hammer. In the conventional printers of the type described, the hammer is directly operated by electromagnets, and an increase in the operating speed of the hammer requires an increase in the size and power of said electromagnets. However, an increase in the size and power of the electromagnets results in an increase in the volume of the printer and requires increased electric power consumption, and is therefore undesirable. To avoid the above-described defects, a device wherein the energy for printing can be obtained from a continuously rotating body is utilized.